Hemoglobinuria

Hemoglobinuria is a condition in which the oxygen transport protein hemoglobin is found in abnormally high concentrations in the urine.^[1] The condition is caused by excessive intravascular hemolysis, in which large numbers of red blood cells (RBCs) are destroyed, thereby releasing free hemoglobin into the plasma.^[2] Excess hemoglobin is filtered by the kidneys, which excrete it into the urine, giving urine a purple color. Hemoglobinuria can lead to acute tubular necrosis which is an uncommon cause of a death of uni-traumatic patients recovering in the ICU.

Hemoglobinuria
Other names	Haemoglobinuria
Structure of hemoglobin
Specialty	Urology, nephrology
Symptoms	Disease, Hemolytic anemia, Proteinuria
Causes	Acute glomerulonephritis; Burns; Renal cancer; Malaria; Paroxysmal nocturnal hemoglobinuria; Microangiopathies, e.g. hemolytic-uremic syndrome (HUS), thrombotic thrombocytopenic purpura (TTP) leading to microangiopathic hemolytic anemia; Transfusion reactions; IgM autoimmune hemolytic anemia; Glucose-6-phosphate dehydrogenase deficiency; Pyelonephritis; Sickle cell anemia; Tuberculosis of the urinary tract; March hemoglobinuria secondary to repetitive impacts on the body, usually the feet; Athletic nephritis secondary to strenuous exercise; Acute lead poisoning

Diagnosis

The diagnosis is often made based on the medical history, blood samples, and a urine sample. The absence of urine RBCs and RBC casts microscopically despite a positive dipstick test suggests hemoglobinuria or myoglobinuria. The medical term for RBCs in the urine is hematuria.

See also

• Hematuria